Not just with friends, but also during my working life I have seen so many people move on, and have moved on many times myself. This is a song about moving on - when you get to the point that where you are doesn't offer what you want and need any more.
But when you make the move you take a risk - it may not be everything you were looking for, and it may just be a small stage in life's journey - or something for longer. Is there a best place for each of us? Or do we make do with what we have?